Wire racks have attained a high degree of commercial acceptance because of the relative ease with which they may be fabricated, the low cost of wire stock and the short time required to fabricate them. Such racks are particularly popular for relatively small and light objects which must be displayed prominently; and to save storage space, such racks are collapsible as shown in my U.S. Pat. No. 3,726,415. Such racks are not generally regarded favorably for heavy duty applications, referred to as such because in such applications, these racks are subjected to rough treatment if not outright abuse. Treated roughly, the welded joints of the racks, typically resistance welded, are prone to failure.
Racks used to hold grocery bags open while they are filled belong in the heavy duty category. It is common experience that groceries including canned goods and the like are loaded into a grocery bag with the emphasis on haste rather than care. As a result, a device such as is shown in U.S. Pat. No. 4,062,170 to hold a plastic bag with integral handle loops open, by inserting tab-shaped protrusion into the loops, was initially made of heavy steel sheet metal. Not surprisingly, the cost of fabricating such devices was discouragingly high considering the economics of the circumstances surrounding their use, and much energy and time was devoted to finding a more economical way.
It eventually became evident that economies in fabrication could be effected if the rack was made of wire for the most part, and such a rack has been constructed as will be described hereinbelow, and placed in service, with unexpectedly discouraging results. The racks broke at the welds. The plastic bags were prone to be ensnared by indentations in the base, or on protruding heads of machine screws used to secure the base to a counter top, and even at the edges of the base. By no means of least importance was the waste of space in cartons in which the racks were shipped.
As is well known, the cost of welding in the fabrication of any welded article is a substantial cost, and it is in the interest of economy to use the least expensive method of welding which will provide the desired strength. As wire stock from which an adequately sturdy rack is made is typically about 0.25" (inch) in diameter, or less, resistance welding is the most practical method of fabrication. Since such welds were less than reliable in service, arc welding the joints was tested, but the arc welded joints were still unsatisfactory and the cost of the racks became prohibitive. Since mechanical fastening means were equally uneconomical, it appeared that the discouraging economics of fabrication would have to be tolerated.
Since the reality of the marketplace dictates that the cost of supplying suitable racks, for use in holding plastic bags open, is to be met from the profits of selling the bags, it is essential that the cost of the racks be minimized.
The wire rack of my invention has succeeded in minimizing cost yet improving performance.